Law enforcement and the courts, who are the only entities with the right to do so.

Dexter's code has no right to exist, because he is not the government. Only the government has the right to institute laws and systems of punishment for breaking them. Only the legal system's code matters. That's the end of it, really.

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"But here you are, in the ninth
Two men out and three men on
Nowhere to look but inside
Where we all respond to PRESSURE!" - Billy Joel